Acute Coronary Syndrome: Drug Induced
Imbalance in myocardial blood supply and oxygen requirement
• Sympathomimetics are associated with myocardial oxygen mismatch due to induced vasoconstriction:
o Cocaethylene is a toxic compound formed by hepatic transesterification of alcohol and cocaine further exacerbates the sympathomimetic effects of cocaine.
o Amphetamines (crank)
o Ephedrine (dietary supplement), pseudoephedrine (decongestant)
o Ma huang (herbal diet supplement)
o Dipivefrin (glaucoma eye drop)
o Phenylpropanolamine (nasal decongestant)
o Methylene 3,4 dioxymethamphetamine (ecstasy)
• Cocaine-induced chest pain also caused by:
o Increased myocardial workload
o Accelerated atherosclerosis
o Activation of platelets and promotion of thrombosis
• Antimigraine therapyâ€”sumatriptan, methysergide, ergotamine, and isometheptene:
o Particularly with cardiac risk factors or known coronary disease
• Calcium channel blockersâ€”nifedipine:
o Reflex tachycardia and vasoconstriction
• Beta-blockers (metoprolol and propanolol):
o Î±-adrenergic mediated coronary vasospasm
• Carbon monoxide found with gas heaters, smoke inhalation, furniture stripping with methylene chloride:
o Decreasing oxygen-carrying capacity
o Shifting the oxyhemoglobin dissociation curve to the left
o Binding to myoglobin
o Used for acromegaly, Parkinson disease, hyperprolactinemia, amenorrhea/galactorrhea, lactation cessation
o Risk increased by predisposing conditions:
Other vasospastic conditions (Raynaud disease or migraine headaches)
• Other dopaminergic agents (dopamine):
o Vasoconstriction and vasospasm
o Vasodilatory properties
o Transient decreases in supine blood pressure
o Increase the risk of cardiac event during sexual activity
• Oral contraceptives:
o Higher incidence of MI in young women with concomitant smoking
Signs and Symptoms
• Chest pain
• Substernal pressure
• Burning sensation
• Sympathomimetic toxidrome symptoms:
o Moist skin
o No urine retention
• Recent ingestion of medication/drug that induces coronary vasospasm
• Cardiac risk factors or known cardiac disease
• Physical exam is usually unrevealing
• Blood pressure (BP) is usually elevated during symptoms
History is critical in diagnosing and differentiating drug-induced and unusual causes of acute coronary syndromes.
o Normal approximately 50% of the time
o Compare to prior tracings
o New ST segment changes or T-wave inversions
o 1-mm depression of the ST segment below the baseline
o 80 msec from the J point
o Helpful in diagnosing other etiologies
• ECG in carbon monoxide poisoning:
o Premature ventricular contractions:
o Nonspecific ST-T wave abnormalities
o Acute MI: ST elevation or depression
• Serial cardiac enzymes
• Troponin may be more helpful.
• Creatine kinase may be elevated in cocaine-induced rhabdomyolysis
• Carboxyhemoglobin level for suspected carbon monoxide (CO) toxicity
• Serum toxicology screening
• Chest radiograph:
o Usually normal
o May show cardiomegaly
o Congestive heart failure
o May identify other etiologies of chest pain such as pneumonia
• Exercise stress testing: Identify underlying atherosclerosis.
• A technetium Tc-99m perfusion scan: myocardial damage/MI
• ECG: wall motion abnormalities
• Gold standard: cardiac catheterization
• Most patients will have angiographically normal coronary arteries.
• Aortic dissection
• Biliary colic
• Esophageal reflux
• Esophageal spasm
• Herpes zoster
• Hiatal hernia
• Mitral valve prolapse
• Myocardial infarction
• Panic disorder
• Peptic ulcer disease
• Pulmonary embolus
• Unstable angina
• Remove patient from contaminated environment if carbon monoxide toxicity is a consideration.
• IV access
• Cardiac monitoring
• Sublingual nitroglycerin for symptom relief
• All chest pain should be treated and transported as a possible life-threatening emergency.
• Avoid Î²-adrenergic antagonists in cases of suspected cocaine use.
• Place patient on a monitor
• IV access should be obtained
• O2: 100% oxygen
• Î²-adrenergic blockers should be avoided in patients who are suspected to have used cocaine.
• Benzodiazepines: cocaine use
• Reduce BP and heart rate.
• Decreasing myocardial oxygen demand
• Heparin or enoxaparin
• Thrombolytics: Use with caution in suspected vasospasm induces acute coronary syndrome
• Cardiac catheterization: diagnostic and/or therapeutic
• Carbon monoxide toxicity:
o 100% O2
o Hyperbarics if
o Carboxyhemoglobin level is >25â€“40%.
o Any period of coma
o Neurologic deficits
o Persistent metabolic acidosis
o Pregnant and carboxyhemoglobin level is >15%.
o Cardiac instability
o Acute MI, unless hemodynamically unstable
• Half-life of carboxyhemoglobin:
o Room air: 300 minutes
o 100% O2: 90 minutes
o Hyperbaric chamber at 3 ATM: 20 minutes
• Aspirin: 160-325 mg PO
• Enoxaparin (Lovenox): 1 mg/kg SC q12h
• Heparin: 80 units/kg IV bolus, then 18 units/kg/hr
• Labetalol: 20 mg IV or 100 mg PO
• Lorazepam: 1-2 mg IV
• Metoprolol: 5 mg IV q5min-q15 min followed by 25-50 mg PO starting dose as tolerated (note: beta-blockers contraindicated in cocaine chest pain)
• Morphine: 2 mg IV, may titrate upward in 2-mg increments for relief of pain assuming no respiratory deterioration and SBP >90 mm Hg
• Nitroglycerin: 0.4 mg sublingual
• Nitroglycerin: IV drip at 5-10 Âµg/min
• Nitropaste: 1-2 inches transdermal
• Tenecteplase: for 60-kg person, 30 mg; >60-69 kg, 35 mg; 70-79 kg, 40 mg; 80-89 kg, 45 mg, >90 kg, 50 mg given IV; or Reteplase, 10 units IV over 2 minutes, repeat in 30 minutes
• Similar to patients with acute coronary syndromes of atherosclerotic origin
• New-onset chest pain
• Rest chest pain
• Accelerated chest pain symptoms
Chronic stable chest pain
1. Lai TI, Hwang JJ, Fang CC, Chen WJ. Methylene 3,4 dioxymethamphetamine-induced acute myocardial infarction. Ann of Emerg Med. 2003;42(6):759-762.
2. Lange RA, Hillis LD. Cardiovascular complications of cocaine use. N Engl J Med. 2001;345:351-358.
3. Manini AF, Kabrhel C, Thomsen. Acute Myocardial Infarction after over-the-counter use of Pseudoephedrine. Ann of Emerg Med. 2005;45(2):213-218.
4. Marius-Nunez AL. Myocardial infarction with normal coronary arteries after acute exposure to carbon monoxide. Chest. 1990;97:491-494.
5. Ottervanger JP, Wilson JH, Stricker BH. Drug-induced chest pain and MI. Reports to a national center and review of the literature. Eur J Clin Pharmacol. 1997;53:105-110.
6. Qasim A, Townend J, Davies MK. Esctasy induced myocardial infarction. Heart. 2001;85(6):E10
7. Tanis BC, van den Bosch MA, Kemmeren JM, et al. Oral contraceptives and the risk of myocardial infarction. N Engl J Med. 2001;345:1787-1793.
8. Wasson S, Jayam VK. Coronary vasospasm and myocardial infarction induced by oral sumatriptan. Clin Neuropharmocol. 2004;27(4):198-200.
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